Wednesday, September 3, 2008

Muddiest Point #2

I am still a little confused about binary representation. I understand that 0s and 1s are used to represent physical data but why only 0s and 1s and not other numbers? And how does a computer interpret binary digits? I guess I am looking for a more physical alphabet that I can understand.

1 comment:

Caitlin Beery said...

Binary representation is using base 2 math. You're probably more familiar with base 10 math.

In base 10 math, there are 10 digits: 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9. In base 2 math (binary), there are only 2 digits: 0 and 1.

Check out http://gwydir.demon.co.uk/jo/numbers/binary/kids.htm to get a good view of how counting in binary works.

As you can see, the columns have different values in binary than they do in base 10. In base ten, the columns (from right to left) are called ones, tens, hundreds, thousands, and ten thousands. In binary, they are ones, twos, fours, eights, and sixteens. There are exponents involved (which I can't figure out how to do in HTML) in the column values.

I don't know about how a computer interprets the binary digits, other than it involves some sort of switch being either ON or OFF, which is expressed using 0s and 1s.